Create [remote]/~/print automatically when using background sessions.

Avoid the need to manually pass the -i option when having background
sessions active and printing multiple files.
Use `rsync` instead of `scp` and drop `-i` install command line option.

Using `rsync` for remote file transfer removes the need to manually
create the remote temp directory `~/print`.
Remove '-i' option from usage message and zsh-autocompletion as well
Update documentation for local forwards
Update zsh-autocompletion for local forwards
Add NOTE: concerning multiple forwards
Merge branch 'master' into local-port-forward

Conflicts:
	uniprint